1982 PHOTOCOPY OF DRAWING CONCENTRATING MILL, FLOW SHEET, APRIL 1, 1924
1982 PHOTOCOPY OF DRAWING CONCENTRATING MILL, FLOW SHEET, APRIL 1, 1924
1982 PHOTOCOPY OF DRAWING, CONCENTRATING MILL, FLOW SHEET, APRIL 1, 1924
1982 PHOTOCOPY OF DRAWING, CONCENTRATOR, FLOW SHEET (no date)
1982 PHOTOCOPY OF DRAWING, CONCENTRATOR, FLOW SHEET, NOVEMBER 15, 1912
1982 PHOTOCOPY OF DRAWING, CONCENTRATING MILL, FLOW DIAGRAM, DECEMBER 15, 1916